Remove bundle container signing support.

It was never implemented and ass-u-mes containers are cabs,
which hopefully won't be the case forever.

Fixes wixtoolset/issues#7490.

src/wix/WixToolset.Sdk/tools/WixToolset.Signing.props

@@ -52,18 +52,6 @@
   -->
   <Target Name="SignMsi" />
 
-  <!--
-  ==================================================================================================
-  SignContainers
-
-    Redefine this target in your project in order to sign your bundle's detached containers.
-
-    [IN]
-    @(SignContainers) - detached container files to sign.
-  ==================================================================================================
-  -->
-  <Target Name="SignContainers" />
-
   <!--
   ==================================================================================================
   SignBundleEngine

src/wix/WixToolset.Sdk/tools/WixToolset.Signing.targets

@@ -62,8 +62,6 @@
       InternalSignMsi;
     </_InternalSignDependsOn>
     <_InternalSignDependsOn Condition=" '$(OutputType)' == 'Bundle' ">
-      GetContainersToSign;
-      InternalSignContainers;
       InscribeBundleEngine;
       InternalSignBundleEngine;
       InscribeBundle;
@@ -96,7 +94,7 @@
 
     <WriteLinesToFile
       File="$(SignedFilePath)"
-      Lines="^$(MSBuildProjectFullPath);@(SignMsm);@(SignCabs);@(SignMsi);@(SignContainers);@(SignBundleEngine);@(SignBundle)"
+      Lines="^$(MSBuildProjectFullPath);@(SignMsm);@(SignCabs);@(SignMsi);@(SignBundleEngine);@(SignBundle)"
       Overwrite="true" />
   </Target>
 
@@ -156,18 +154,6 @@
       Outputs="$(SignedFilePath)"
       Condition=" '@(SignMsi)' != '' " />
 
-  <Target
-      Name="GetContainersToSign"
-      Inputs="@(SignTargetPath)"
-      Outputs="$(SignedFilePath)">
-    <!-- TODO: implement signing detached containers -->
-  </Target>
-
-  <Target
-      Name="InternalSignContainers"
-      DependsOnTargets="SignContainers"
-      Condition=" '@(SignContainers)' != '' " />
-
   <Target
       Name="InternalSignBundleEngine"
       DependsOnTargets="SignBundleEngine"
@@ -224,8 +210,7 @@
   ================================================================================================
   InscribeBundleEngine
 
-    To be called after signing a bundle's detached containers. Also removes attached container
-    so engine can be signed without attached container.
+    Removes attached container so engine can be signed without attached container.
 
     [IN]
     @(SignTargetPath) - The bundle to inscribe.